Serum adipokine levels in the obese people.

We read the article by Onat et al 1 on the association of serum adiponectin with obesity, hyperinsulinemia, lipoproteins, inflammatory markers and sex hormone binding globulin. In a relatively large population sample, they report some interesting results based mostly on statistical associations that, to our understanding, might not wholly represent the studied population itself.

As we know, other than the body fat content, degree of insulin sensitivity and age, there are some more major determinants of circulating adiponectin. First, we clearly know that not only the people with diabetes mellitus but also those with impaired glucose tolerance have lower adiponectin level compared to healthy controls 2. Second, increased blood pressure is a condition with decreased adiponectin concentration 3,4. Third, as the authors noticed in their model, medications for metabolic diseases such as diabetes, hypertension or dyslipidemia significantly alter blood level of adipokines 5-7.

The authors state in their paper that blood adiponectin has no association with antidiabetic, antihypertensive or hypolipidmic medications. However, no information was given about the fasting glucose level or glucose tolerance status of the other participants without documented diabetes most of whom were obese. Moreover, it appears that newly diagnosed or insufficiently treated diabetes or hypertension was categorized in the same group with established disease, which needs to be argued further. Therefore, it would be appreciated if the authors could present some more data adjusted for major confounders including fasting glucose, prediabetes and newly diagnosed or untreated diabetes and hypertension. This could provide the readers of the journal clearer information in relation to the link between adiposity, adipokines and insulin sensitivity.